Dounreay’s purpose was to research and develop more efficient ways to generate electricity from uranium and plutonium.
A variety of fuel types were tested in reactors and examined over a 40-year period.
Approximately 100 tonnes of material (‘spent’ and unirradiated) had accumulated at the site by 1994 when the research programme came to an end.
A small amount belongs to foreign operators and arrangements were made for this to be returned.
Most of the material belongs to the Nuclear Decommissioning Authority (NDA), a non-departmental public body of the UK Government, and is a national asset.
Dounreay is closing down, so decisions are being taken about where and how the NDA's nuclear material will be managed in future.
The nuclear material stock can be divided into two categories:
- Dounreay Fast Reactor breeder
- Exotic fuel and nuclear materials
The Dounreay Fast Reactor was designed to breed its own fuel. Breeder elements made from natural uranium were placed in a zone around the reactor core to produce plutonium.
Some of this material has now been sent to Sellafield where the plutonium could be re-used; the remainder will be removed from the reactor and transported to Sellafield as part of Dounreay’s closure programme.
This group of nuclear materials can be divided into four categories:
- Unirradiated plutonium bearing fuels consisting of plutonium, mixed uranium and plutonium oxide and mixed uranium and plutonium carbide fuels
- Unirradiated high enriched uranium fuels consisting of uranium oxides, uranium metal, uranium alloy, uranium tetrafluoride, uranium hexafluoride and other miscellaneous enriched uranium fuels
- Irradiated fuels, comprising oxide and carbide fuel consisting mainly of Prototype Fast Reactor (PFR) fuel and the HELIOS material that was irradiated in experimental work
- Uranium-containing non-fuel based materials known as uranics which have been produced as a result of fuel cycle operations, including depleted and natural uranium
Following consultation, the NDA ‘s preferred option was to remove the fuel from Dounreay.
The programme to remove the exotic fuels is expected to take until the early 2020s to complete.
Over a 40 year period, Dounreay reprocessed spent fuel for UK and overseas reactors.
However, due to a breakdown in a recycling plant, less than a tonne of foreign fuel could not be recycled and returned to the countries of origin.
As part of the site closure programme, the NDA sought to close out the historic contracts with foreign governments, in a way that complied with UK government policy.
As the contracts do not allow the fuel to be returned untreated, it has been agreed in principle instead to send each customer an amount of new fuel and waste from UK stocks, equivalent to what would have been produced if the fuel had been reprocessed, with the UK retaining the spent fuel. The detailed arrangements are now the subject of negotiations. This is known as "advance allocation".
In addition to spent fuel, UKAEA also had contracts in place for unirradiated fuel belonging to other countries. International Nuclear Services (INS), a subsidiary of the NDA, is now responsible for concluding these contracts.
The total amount of waste arising from the contracts is equivalent to approximately 500 of the standard 500-litre waste containers used at Dounreay. This represents 2% of all the higher activity waste at Dounreay.
In 2012, the Scottish and UK Governments decided INS could offer waste substitution in its negotiations to close out these contracts.
Global Threat Reduction Initiative
The US Government removed irradiated and un-irradiated uranium from Georgia in 1998 for security reasons.
The UK Government agreed to accept the material at Dounreay, as this was only one of a few places in the world that could handle this material and where, at the time, there was potential for the fissile material to be recovered for re-use in support of nuclear medicine.
The unirradiated highly-enriched uranium is “US-obligated”.
Under the Global Threat Reduction Initiative, US-obligated and Russia-obligated highly-enriched uranium is being repatriated, so in 2010 this material was removed from Dounreay and taken to the United States.
Discussion about options for the remaining ex-Georgia material is continuing.
As part of the site closure programme, the NDA consulted on the options for its remaining nuclear fuel and re-usable material at Dounreay, culminating in a decision to return it to national stocks.
DSRL started to remove the NDA's nuclear fuel and material in 2012 and expects this work to continue until the early 2020s.
Nuclear materials can be transported by road, rail, sea and air, depending on the type of material and the container being used to transport it.
Dounreay recognises that the transport of radioactive material by air, sea and land raises issues of public interest about safety, security and environmental protection.
If you have concerns or questions about the removal of radioactive material from Dounreay during its closure, we're happy to provide more information (subject to constraints on security) and arrange to meet individuals or groups to listen to their views.
The standards governing the transport of nuclear material are set by the International Atomic Energy Agency.
These standards are the basis for legislation and regulation drawn up by national governments. In the UK, the Department of Transport is the competent authority. Regulation in the UK is consolidated in the Office for Nuclear Regulation.
Our arrangements for the transport of this material must comply with the national legislation and our plans are subject to rigorous independent regulation designed to ensure the public and environment are protected from harm at all times.
In the event of an accident in the UK, the RADSAFE network provides immediate technical support to the 999 first-responders.
DSRL is part of RADSAFE - a network of operators that provides mutual aid in the event of an accident.
The UK has an armed police force dedicated to the security of nuclear materials.
The Civil Nuclear Constabulary (CNC) is in charge of protecting civil nuclear sites and nuclear materials in England, Scotland and Wales.
It's Strategic Escort Group have helped safely transit nuclear material over 61,000 miles in the last four years.
Transport has played an important part in the story of Dounreay, bringing nuclear materials to and from the site during four decades of research and development.
Today, as the site closes down, those materials are leaving for the last time, signalling the end of nuclear transports in the Highlands of Scotland.
In addition to the removal of nuclear fuel and some foreign-owned radioactive waste, other transports of radioactive material needed to close down the site include:
- Radioactive particles will be transported to the site so long as the particle recovery and monitoring programmes continue on nearby beaches.
- Some equipment needed to decommission particular facilities and process wastes contains radioactive sources. We send radioactive sources for calibration and recertification for quality control purposes.
- Some equipment purchased for the management of radioactive waste contains natural or depleted uranium.
- Some lightly radioactive materials may be removed for recycling or specialist decontamination elsewhere, such as lead bricks, mercury and sodium.
- Samples such as soil, concrete and graphite may sometimes be sent to specialist labs for characterisation and independent verification